By studying the brains of animals watching movies of natural scenes, the researchers found that the actions of inhibitory neurons help the brain save energy by suppressing non-essential visual information and processing only critical information.

Specifically, the inhibitory cells in the visual cortex control how excitatory cells interact with one another.

"It's called the iceberg phenomenon, where only the tip is sharply defined yet we are aware that there is a much larger portion underwater that we cannot see," co-senior author David McCormick, a professor of neurobiology at the Yale School of Medicine and a researcher at the Kavli Institute of Neuroscience, said in a Yale news release.

"These inhibitory neurons set the water level and control how much of the iceberg we see. We don't need to see the entire iceberg to know that it is there," he explained.

The study was published in a recent issue of Neuron.

It's long been known that the brain uses the majority of the body's energy, but scientists didn't know how the brain can operate both efficiently and reliably as it processes a steady deluge of sensory input.